WASHINGTON: The United States has ruled out the possibility of the missing Malaysian plane landing at its Indian Ocean base in Diego Garcia.

"I'll rule that one out," White House Press Secretary Jay Carney told reporters when asked about such news reports appearing mainly in the Chinese press.

Carney said the Malaysian government has the lead in this investigation and the U.S. officials are in Kuala Lumpur working closely with the Malaysian government on the investigation.

"This is a difficult and unusual situation, and we are working hard, in close collaboration with the Malaysian government and other partners, to investigate a number of possible scenarios for what happened to the flight. Our hearts of course go out to the families of the passengers. They are in a truly agonizing situation," he said.

The United States remain fully committed to assisting the Malaysians and working with its international partners on this investigation, on this effort.

"And we are providing assistance through the NTSB, through the FAA and through the FBI. We are in a close, collaborative relationship as regards this investigation," he said in response to a question.

Meanwhile, U.S. State Department Spokesperson Jen Psaki said the focus now was on new search areas announced by the Malaysian Prime Minister over the weekend, which are based on a detailed, highly technical and innovative analysis of the potential flight path.

The U.S. Navy is repositioning the P-8A's Poseidon to Perth, Australia to conduct searches along the southern corridor. And additionally, P-3C Orion will continue to conduct its mission to search west of Indonesia. And they've also made the determination that the USS Kidd's capabilities did not match current task, and it has been reassigned, she said.

The mystery of the missing plane from Kuala Lumpur to Beijing since March 8 continued to baffle aviation and security authorities who have not succeeded in tracking the aircraft despite deploying hi-tech radar and other gadgets.